1. Field of the Invention
The present invention relates to electrophotographic image forming apparatuses, and particularly relates to misregistration correction control in image forming apparatuses.
2. Description of the Related Art
A so-called “tandem” type image forming apparatus, in which image forming units are provided independently for each color in order to print at high speeds, is known as a type of electrophotographic image forming apparatus. Such tandem-type image forming apparatuses are configured so that images are sequentially transferred from each color image forming unit onto an intermediate transfer belt and the images are then transferred from the intermediate transfer belt onto a recording medium at one time. In such an image forming apparatus, color misregistration (misregistration) can arise when superimposing the images due to mechanical factors in each color image forming unit. The image forming apparatus therefore carries out misregistration correction in order to form high-quality images.
Misregistration occurs when the positions, shapes, and so on of components involved in image formation change due to changes in temperature in the image forming apparatus resulting from continuous printing. It is thus necessary to execute misregistration correction periodically, even when continuous printing is underway. However, a user cannot print while the misregistration correction is underway, resulting in downtime for the user. Accordingly, there is demand for an image forming apparatus that improves the usability by reducing such downtime.
Japanese Patent Laid-Open No. 2012-032777 discloses a configuration that corrects misregistration by detecting an electrostatic latent image for correction formed on a photosensitive member in order to reduce downtime.
However, although the configuration disclosed in Japanese Patent Laid-Open No. 2012-032777 can correct misregistration originating on the photosensitive member, the configuration cannot correct misregistration originating on an intermediate transfer belt.